The 1992 crisis proved that the existing system was unstable. Not moving forward to the euro would have set up Europe for even more disruptive crises.

The 24% unemployment reached at the depths of the Great Depression was no picnic.

Across the continent, political divisions are deepening. For all of these reasons, the specter of a euro zone collapse has not been dispatched.

While holding the eurozone together will be costly and difficult and painful for the politicians, breaking it up will be even more costly and more difficult.

Southern Europe has not done enough to enhance its competitiveness, while northern Europe has not done enough to boost demand. Debt burdens remain crushing, and Europe's economy remains unable to grow.

More than the Big Mac, Coca Cola, or Levi's 501 jeans, the dollar is surely the United States' signature export.

Why was there so much work-sharing in the 1930s? One reason is that government pushed for it. In his memoirs, President Herbert Hoover estimated that as many as two million workers avoided unemployment as a result of his efforts to promote work-sharing.